Electric timing switch



V. E. TAMBURR ET AL ELECTRIC TIMING SWITCH) Filed Sept. 10, 1941 April20; 1943.

2 Sheets-Sheet l INVENTOR5 WM ATTORNEY April 20, 1943. v. E. TAMBURRETAL ELECTRIC TIMING SWITCH Filed Sept. 10, 1941 2 Sheets-Sheet 2 14 I hI 1Q Patented Apr. 20, 1943 UNITED STATES PATENT OFFICE ELECTRIC TIMINGSWITCH Jersey Application September 10, 1941, Serial No. 410,266

10 Claims.

This invention relates in general to electric timing devices, forexample to close an electric circuit, maintain the circuit closed for apredetermined period of time and then automatically open the circuit.More particularly, the invention contemplates a device of this characterof the type that comprises a timing selector or timing mechanism whichincludes a setting contact to be manually set, a timing contact rotatedby a synchronous electric motor relatively to the setting contact arm tocooperate therewith for determining the length of the period duringwhich the circuit is to remain closed. One object of our invention is toprovide a novel and improved coupling or connection between thesynchronous electric motor and the timing contact arm a novel andimproved construction and combination of a synchronous electric motor, atiming arm of the general character described, and a gear train betweenthe motor and said timing arm, wherein a part of said gear train shallbe actuated automatically by the motor upon starting thereof toautomatically connect the motor to the timing arm and shall beautomatically disconnected from the timing arm upon stopping of themotor, thereby to provide a simple and reliable construction and avoidthe necessity for the use of auxiliary electromagnets and clutchesactuated thereby for connecting the motor to the timing arm.

Another object is to provide a novel and improved construction andcombination of a timing mechanism of the character described with relayswitches for controlling respectively a solenoid for holding th relayswitches in closed position, the synchronous electric motor and theoutput circuit or the circuit the period of closing of which is to becontrolled, whereby a simple, reliable and inexpensive timing switchmechanism may be obtained.

Other objects, advantages and results of the invention will appear fromthe following description when read in conjunction with the accompanyingdrawings in which Figure 1 is a rear elevational view of a timing switchmechanism embodying the invention, a portion of the housing of theswitch mechanism being broken away for clearness in illustration.

Figure 2 is a side elevational view of the mechanism taken on the line2-2 of Figure 1,

Figure 3 is a top plan view of the mechanism.

Figure 4 is a fragmentary vertical sectional view on the line 4-4 ofFigure 3.

Figure 5 is a transverse sectional view on the line 5-5 of Figure 1.

Figure 6 is a fragmentary horizontal sectional view on the line 66 ofFigure 1, showing the motor disconnected from the timing arm.

Figure 7 is a similar view showing the motor connected to the timingarm.

Figure 8 is a sectional view on the line 38 of Figure 6, and

Figure 9 is a wiring diagram of the switch mechanism.

An important feature of our invention is the timing selector or timingmechanism and the actuating means therefor, which may be used in variousways with various types of relay switches and circuits, depending uponthe particular use for which the timing mechanism is to be employed.

For the purpose of illustrating the principles of the invention, we haveshown the invention as embodied in a timing mechanism which includes aframe or chassis comprising two plates l and 2 that are rigidlyconnected together by spacing rods 3 that are connected to the plates byscrews 4. This chassis or frame may be enclosed in a suitable casing 53which is only fragmentarily shown in the drawings.

A time setting arm 6 is disposed between the plates and rigidlyconnected to a stub shaft I that is rotatable in a bearing 8 that issecured in the plate I and projects through an opening 9 in one wall ofthe casing 5. Exterior of th casing, the shaft 1 has an operating knobl0 connected thereto that has a pointer H to cooperate with a suitablescale on the wall of the casing in known manner for determining thelocation of the setting arm. The setting arm carries an electricalcontact l2 to cooperate with a similar contact l3 carried by a timingcontact arm I4 that is shown as secured to a shaft l5 preferably ofelectrical insulating material which is journaled in bearings l6 and I!that are mounted in a gear casing [8 which is secured as by screws orrivets H] to the outer side of the other plate 2. The timing arm I4 isarranged to rotate relatively to the setting arm 6 so that at some pointin said rotation the contacts l2 and I 3 will be brought into engagementwith each other. The timing arm M is rotated toward the contact I2 by asynchronous electric motor generally designated A and is rotated in theother direction by a spiral spring 28 one end of which is fixedlyconnected to the hub 2| of the timing arm as at 22 (see Figures 4 and6), while the other end is connected as by studs 23 to the inner side ofthe plat 2.

The motor A is of a generally known type, for exampl as shown in PatentNo. 1,977,185 dated October 16, 1934, but the present motor differs fromthat disclosed in the patent primarily in that the rotor 24 of the motorA is normally located so that the armature 25 is out of the magneticfield of the stator windings, and the armature and rotor areelectromagnetically actuated along the axis of rotation of the rotor bya magnetic attraction when the field windings are energized.

More particularly, the rotor 24 comprises a disc, for example ofaluminum, mounted on a shaft 26 that is journaled and longitudinallymovable in the stator frame. The rotor or disc has a perimetral flangeon the inner side of which the armature 25 is mounted. The end of theshaft 28 opposite the rotor 24 is normally engaged by one end-of aspring 2,? the other end of which is secured in the gear casing I18 asat 28, so that the rotor 24 is normally :moved into :a position tolocate the armature 25 at one side of th magnetic field of the statorthat is generally designated 29. When the stator windings are energizedthe magnetic field attracts the armature 25 so as to move the latterinto the plane of the field, asthe result of which the shaft 25 is movedlongitudinally against the influence of the spring 21, as shown inFigure 7.

The shaft 26 carries a pinion 30 to mesh with a gear 3| that isjournaled in th gear casing I 8. Normally, when the motor A is at rest,the pinion 30 is out of mesh with the gear 3|, but when the motor isstarted, the pinion is moved into mesh with said gear so as to drive thelatter. Rigidly connected with the gear 3| is a pinion 32 with whichmeshes'another gear 33 which rigidly carries a pinion 34 that mesheswith another gear 35 which in turn carries another pinion 35 whichmeshes with a gear 37 that is rigid ly connected to the shaft I on whichthe timing arm I4 is mounted.

With this construction, it will be observed that normally the motor A isunconnected with the timing arm I4, but when the motor is started, the

pinion 35 on the motor shaft is automatically engaged with the gear 3|so as to drive th train of gears and pinions 323| and rotate the timingarm I4 to move the contact I3 toward the contact I2. According to theinvention, as will be hereinafter more fully described, the circuitthrough the motor is broken upon engagement of the contacts I3 and I2whereupon the spring 21 automatically disengages the pinion 30 from thegear 3| so that the timing arm is is disconnected fromtthe motor andfree for rotation in the opposite direction to its initial position bythe spiral spring 26. Preferably a stop lug 3B is provided on the insideof th plate 2 to be abutted by a stud 39 on the timing arm for limitingrotation of th timing arm under influence of the spring 20. It is alsodesirable that a lug 40 be provided on the inside of the plate I forlimiting the rotation of the setting arm 6 for example, this stop maycorrespond to the zero position of the setting arm.

From the foregoing it will be understood that the period during whichthe control circuit is to remain closed, will be determined by the timerequired for movement of the timing arm I4 from its initial or startingposition into contact cured on the plate 2.

with the setting arm 6, and the operator will initially set the settingarm 6 for the desired time interval by manipulation of the handle I9 andpointer I I with respect to the dial or graduations on the casing 5.

The timing mechanism is shown as combined with a push button switch 4|of known construction that is mounted on the plate I, and a plurality ofrelay switches AA, BB and CC. These relay switches are operatedsimultaneously by one and the same solenoid 42 which is secured on theoutside of the plate 2 and with which cooperates an armature 43 that ishingedly connected at M on a bracket 45 which is in turn se- Thearmature is normally influenced away from the solenoid by a coil spring46. One switch includes a stationary contact strip 51 and a cooperatingmovable spring contact 48, while another switch includes a fixed contact49 and a cooperating movable spring contact 59. The third switchincludes a fixed contact 5| and a cooperating movable spring contact5.2. The movable contact strips 48, 50 and 52 are actuated by thearmature 43 into con-tact with their respective fixedcontact strips, thearmature having con-nected thereto a strip of insulating material 53which has slots 54 one to loosely receive the free end of each of themovable contact strips.

The timing mechanism and these switches are shown as connected in anelectric circuit that is diagrammatically illustrated in Figure 8, theline wires being designated L and LL. It will be observed that th timingarm I4 is grounded on the plate 2. The other plate is insulated from theplate 2 as by insulating washers 55, and a conducting strip 55electrically connects one of the spacing rods .3 with the setting arm-6, said spacing rods being connected in the circuit by circuit wires asindicated at 51. The circuit is such that the push button switch 4| wheninitially closed causes energization of the solenoid c2 and consequentactuation of the relay switches. One of the relay switches BB controlsthe circuit through the solenoid so as to hold all of the relay switchesclosed after they have once been closed by actuation of the push buttonswitch. Another relay CC controls the synchronous electric motor A,while the third relay AA controls the output circuit or the circuit thetime of closing of which is to be controlled. For the purpose ofillustration we have shown an electric lamp E in this output circuit.

A resistor F is included in circuit with the relay switch BB thatcontrols the solenoid so as to insure deenergization of the solenoidwhen the contact I3 of the timing arm engages the contact I2 of thesetting arm, an thereby open all of the circuits at the end of thepredetermined period of time.

It will be understood that the push button switch is only for startingthe mechanism and to cause closing of the relay switches, and after thishas been efiected, the push button switch is released to open position.Thereafter, the relay switches will automatically be held closed so thatthe motor A will be continuously driven and the output circuit will beclosed until the timing arm contact I3 engages the setting arm contactI2, whereupon all of the circuits will be automatically opened.

If desired, a toggle switch 58 may be included in the circuit so thatthe output circuit may be entirely manually controlled independently ofthe timing mechanism.

rality of cooperative elements one of which is capable of being engagedwith and disengaged from another to start and stop respectively said;movement of said switch, said motor including a stator and a rotorhaving an armature and- Which is movable axially in opposite directionsrelatively to said stator to locate said armature in and out of themagnetic field of said stator re spectively, said rotor being moved inone of said directions by magnetic influence of said stator upon saidarmature as the stator is energized to start the motor, said one gearingelement being connected to and movable with said rotor to en} gage saidother gearing element upon movement of said rotor in said direction tomove said switch into said one position, means for moving said rotor inthe other direction upon deenergization of said stator to disengage saidone gearing eles ment from the other, and means for actuating saidswitch into its other position upon said disengagement of said onegearing element from the other gearing element.

2. The electric timing mechanism set forth in claim 1 wherein said rotorof the electric motor is mounted on a shaft that is axially movable andsaid one gearing element is mounted on said shaft;

3. The electric timing mechanism set forth in claim 1 wherein said onegearing element is a pinion and said other gearing element is a gear,said rotor of the electric motor is mounted on an axially movable shaftand said one gearing element is mounted on said shaft and moved into andout of mesh with said gearing element upon movement of said shaft inopposite directions respectively.

4. The electric timing mechanism set forth in claim 1 wherein said onegearing element is a pinion and said other gearing element is a gear,said rotor of the electric motor is mounted on an axially movable shaftand said one gearing element is mounted on said shaft and moved into andout of mesh with said gearing element upon I.

movement of said shaft in opposite directions respectively, and saidmeans for moving said rotor to disengage said one gearing element fromthe other is a spring abutting one end of said shaft.

5. An electric timing mechanism comprising "a switch including twocontact arms one of which is rotatable toward and from the other, a,shaft on which said rotatable arm is mounted, gearing including aplurality of cooperative elements one of which is operatively connectedto said shaft while a second of which is capable of being engaged withand disengaged from a third element to start and stop respectivelymovement of said rotatable contact arm toward the other contact arm, a,synchronous electric motor including a stator, a rotor shaft and a rotormounted on said shaft and carrying an armature, said shaft being axiallymovable in opposite directions to locate said armature in and out of themagnetic field of the stator, respectively, said rotor being moved intosaid magnetic field'by magnetic influence of said stator upon thearmature as the stator is energized to start the motor, said secondgearing element being connected to and movable with said shaft to engagesaid third gearing element upon starting of the motor to move saidrotatable contact arm toward the other contact arm, a spring abuttingsaid rotor shaft to move the latter upon deenergization of said statorand disengage said second gearing element from the third gearing elementto stop movement of said rotatable contact arm toward the other contactarm, and a spring for actuating said rotatable contact arm away fromsaid other contact arm upon said disengagement of the second gearingelement from the third gearing element.

6. The electric timing mechanism set forth in claim 5 wherein saidsecond gearing element is a pinion and the third gearing element is agear.

7. An electric timing mechanism comprising a. timing switch, gearing tomove said switch into one of two positions upon movement of said gearingin one direction, an electric motor for driving said gearing, saidgearing including a plurality of cooperative elements one of which iscapable of being engaged with and disengaged from another to start andstop respectively said movement of said switch, an operative connectionbetween said motor and said one gearing element to cause engagement ofthe latter with said other of said gearing elements automatically uponstarting of said motor to move said switch into said position, means todisengage said one gearing element from the other upon stopping of saidmotor, means to actuate said switch into the other positionautomatically upon stopping of said motor, a circuit including saidtiming switch, said motor, two relay switches including a commonsolenoid, a resistor and a push-switch, said push-switch being connectedin circuit with said solenoid whereby said solenoid is energized toclose said relay switches upon closing of said push-switch, and one ofsaid relay switches and said resistor being connected in circuit withsaid solenoid and said timing switch whereby to maintain said solenoidenergized while said timing switch is open and to deenergize saidsolenoid when said timin switch is closed, said motor being controlledby the other relay switch.

8. The combination set forth in claim 7 with the addition of a thirdrelay switch actuated by said solenoid, and an output circuit controlledby said third relay.

9. The electric timing mechanism set forth in claim 7 with the additionof a circuit including said timing switch, said motor, two relayswitches including a common solenoid, a resistor and a push-switch, saidpush-switch being connected in circuit with said solenoid whereby saidsolenoid is energized to close said relay switches upon closing of saidpush-switch, and one of said relay switches and said resistor beingconnected in circuit with said solenoid and said timing switch wherebyto maintain said solenoid energized while said timing switch is open andto deenergize said solenoid when said timing switch is closed, saidmotor being controlled by the other relay switch.

10. An electric timing mechanism including a timin switch, mechanismincluding an electric motor for operating said switch into closedposition, means for operating the switch into open position uponstopping of said motor, a circuit including said timing switch, saidmotor, two relay switches including a common solenoid, a resistor and apush-switch, said push-switch being connected in circuit with saidsolenoid whereby said solenoid is energized to close said relay switchesupon closing of said push-switch, and one of said relay switches andsaid resistor being connected in circuit with said solenoid and said 5the other relay switch.

VICTOR E. TAMBURR LAWRENCE L. NEIDENBERG.

